Atmosic Side-Load Key (SLKEY) Tool

It is a simple command line utility to manage private keys stored in RRAM memory slots on Atmosic devices. The tool supports reading and writing individual keys or all 8 slots at once, currently supports Windows and Linux platforms.

The table below lists the available actions of SLKEY. Detailed descriptions of each action can be found in West slkey command section.

Command Explanation
-h, --help List available commands
read Read private key from a specific slot
write Write private key to a specific slot
read_all Read all private keys from slots 0-7
write_all Write all private keys from a file to slots 0-7

Before You Begin

Before running the SLKEY tool, ensure the following items are prepared:

1. Private Key Storage Information

Private keys are stored in 8 slots (0-7) in RRAM memory. Each slot can hold a 32-byte private key.

Memory Layout:

  • RRAM Base Address: 0x10000000

  • Private Key Start Offset: 0x8FF00

  • Slot Size: 32 bytes (256 bits)

  • Total Slots: 8 (slots 0-7)

  • Total Key Area: 256 bytes

Slot Address Calculation:

Slot Address = 0x8FF00 + (Slot Index × 32)

Slot 0: 0x8FF00
Slot 1: 0x8FF20
Slot 2: 0x8FF40
Slot 3: 0x8FF60
Slot 4: 0x8FF80
Slot 5: 0x8FFA0
Slot 6: 0x8FFC0
Slot 7: 0x8FFE0

2. Key Data Format

Private keys can be provided in two formats:

Hex String Format (for single key write):

10eb3d60be71ca15f0ae732b81777d85072c351fd708613ba310982df4df1409

File Format (for write_all):

  • Binary format: 256 bytes (8 keys × 32 bytes each)

The file must contain raw binary data (hex bytes), not ASCII text.

Note

Keys shorter than 32 bytes will be automatically padded with 0xFF at the end.

3. Partition Information File

The partition_info.map file is required to locate the private key storage offset. The tool extracts the SEC_SIDELOAD_KEYS_OFFSET parameter.

For example (partition_info.map):

SEC_SIDELOAD_KEYS_OFFSET=0x8FF00
SEC_SIDELOAD_KEYS_SIZE=0x100

West slkey Commands

Use the following command to view usage details:

Syntax

west slkey --help

Example

$ west slkey --help
usage: west slkey [-h] {read,write,read_all,write_all} ...

Atmosic Side-Load Key (SLKEY) management tool

positional arguments:
  {read,write,read_all,write_all}
                        sub-command to run
    read                Read private key from specified slot
    write               Write private key to specified slot
    read_all            Read all private keys from slots 0-7
    write_all           Write private keys from file to slots 0-7

options:
  -h, --help            show this help message and exit

Read a Single Private Key

Syntax

west slkey read [-h] --slot_index SLOT_INDEX [--device DEVICE_ID] [--dl] [--jlink] [--board BOARD] [-p PARTITION_FILE]

Required parameters:

  • --slot_index Key slot number (0-7)

  • --device Serial number of the programmer (see serial)

  • --board Atmosic device (see board)

  • -p Partition_info.map file path

Optional parameters:

  • --dl Specify if using a Download Board (DL) interface

  • --jlink Specify if using a J-Link interface

Example

$ west slkey read --slot_index 0 --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -p build/settings/zephyr/partition_info.map
SEC_SIDELOAD_KEYS_OFFSET: 0x8FF00
Using ATM OpenOCD 'D:\Project\zephyr\zephyrproject\modules\hal\atmosic_lib\tools\openocd\bin\Windows_NT\openocd'
Inferred OpenOCD config for board 'ATMEVK-3405-WQK-5': D:\Project\zephyr\zephyrproject\zephyr/../openair/modules/hal_atmosic/ATM34xx/rev-5/openocd/atmx3_openocd.cfg
Reading private key from slot 0 (address 0x8FF00) from RRAM...
Slot 0 (32 bytes): 10eb3d60be71ca15f0ae732b81777d85072c351fd708613ba310982df4df1409

Write a Single Private Key

Syntax

west slkey write [-h] --slot_index SLOT_INDEX --data DATA [--device DEVICE_ID] [--dl] [--jlink] [--board BOARD] [-p PARTITION_FILE]

Required parameters:

  • --slot_index Key slot number (0-7)

  • --data Private key as hex string (will be padded to 32 bytes with 0xFF if shorter)

  • --device Serial number of the programmer (see serial)

  • --board Atmosic device (see board)

  • -p Partition_info.map file path

Optional parameters:

  • --dl Specify if using a Download Board (DL) interface

  • --jlink Specify if using a J-Link interface

Example

$ west slkey write --slot_index 1 --data 10eb3d60be71ca15f0ae732b81777d85072c351fd708613ba310982df4df1409 --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -p build/settings/zephyr/partition_info.map
SEC_SIDELOAD_KEYS_OFFSET: 0x8FF00
Using ATM OpenOCD 'D:\Project\zephyr\zephyrproject\modules\hal\atmosic_lib\tools\openocd\bin\Windows_NT\openocd'
Inferred OpenOCD config for board 'ATMEVK-3405-WQK-5': D:\Project\zephyr\zephyrproject\zephyr/../openair/modules/hal_atmosic/ATM34xx/rev-5/openocd/atmx3_openocd.cfg
Writing private key to slot 1 (address 0x8FF20) to RRAM...
Successfully wrote private key to slot 1

Read All Private Keys

Syntax

west slkey read_all [-h] [-o OUTPUT] [--device DEVICE_ID] [--dl] [--jlink] [--board BOARD] [--rram] [-p PARTITION_FILE]

Required parameters:

  • --device Serial number of the programmer (see serial)

  • --board Atmosic device (see board)

  • -p Partition_info.map file path

Optional parameters:

  • -o, --output Optional output file to save all keys (256 bytes total)

  • --dl Specify if using a Download Board (DL) interface

  • --jlink Specify if using a J-Link interface

Example

  1. Read all slots and display

    $ west slkey read_all --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -p build/settings/zephyr/partition_info.map
SEC_SIDELOAD_KEYS_OFFSET: 0x8FF00
Using ATM OpenOCD 'D:\Project\zephyr\zephyrproject\modules\hal\atmosic_lib\tools\openocd\bin\Windows_NT\openocd'
Inferred OpenOCD config for board 'ATMEVK-3405-WQK-5': D:\Project\zephyr\zephyrproject\zephyr/../openair/modules/hal_atmosic/ATM34xx/rev-5/openocd/atmx3_openocd.cfg
Reading all private keys from slots 0-7 from RRAM...
Reading 256 bytes from address 0x8FF00...

======================================================================
All Slot Data:
======================================================================
Slot 0: 10eb3d60be71ca15f0ae732b81777d85072c351fd708613ba310982df4df1409
Slot 1: 10eb3d60be71ca15f0ae732b81777d85072c351fd708613ba310982df4df1409
Slot 2: 404142434445464748494a4b4c4d4e4f505152535455565758595a5b5c5d5e5f
Slot 3: 606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f
Slot 4: 808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f
Slot 5: a0a1a2a3a4a5a6a7a8a9aaabacadaeafb0b1b2b3b4b5b6b7b8b9babbbcbdbebf
Slot 6: c0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedf
Slot 7: e0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f8f9fafbfcfdfeff
======================================================================

Successfully read all 256 bytes from slots 0-7

  2. Read all slots and save to file

    $ west slkey read_all --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -o all_keys.bin -p build/settings/zephyr/partition_info.map
SEC_SIDELOAD_KEYS_OFFSET: 0x8FF00
Using ATM OpenOCD 'D:\Project\zephyr\zephyrproject\modules\hal\atmosic_lib\tools\openocd\bin\Windows_NT\openocd'
Inferred OpenOCD config for board 'ATMEVK-3405-WQK-5': D:\Project\zephyr\zephyrproject\zephyr/../openair/modules/hal_atmosic/ATM34xx/rev-5/openocd/atmx3_openocd.cfg
Reading all private keys from slots 0-7 from RRAM...
Reading 256 bytes from address 0x8FF00...

======================================================================
All Slot Data:
======================================================================
Slot 0: 10eb3d60be71ca15f0ae732b81777d85072c351fd708613ba310982df4df1409
Slot 1: 10eb3d60be71ca15f0ae732b81777d85072c351fd708613ba310982df4df1409
Slot 2: 404142434445464748494a4b4c4d4e4f505152535455565758595a5b5c5d5e5f
Slot 3: 606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f
Slot 4: 808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f
Slot 5: a0a1a2a3a4a5a6a7a8a9aaabacadaeafb0b1b2b3b4b5b6b7b8b9babbbcbdbebf
Slot 6: c0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedf
Slot 7: e0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f8f9fafbfcfdfeff
======================================================================

Successfully saved all 256 bytes to all_keys.bin

Write All Private Keys from File

Syntax

west slkey write_all [-h] -f FILENAME [--device DEVICE_ID] [--dl] [--jlink] [--board BOARD] [-p PARTITION_FILE]

Required parameters:

  • -f, --filename Path to file containing private keys for slots 0-7

  • --device Serial number of the programmer (see serial)

  • --board Atmosic device (see board)

  • -p Partition_info.map file path

Optional parameters:

  • --dl Specify if using a Download Board (DL) interface

  • --jlink Specify if using a J-Link interface

Note

The file must be in binary format containing 256 bytes (8 keys × 32 bytes each). The file should contain raw binary data (hex bytes), not ASCII text.

Example

$ west slkey write_all -f keys.bin --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -p build/settings/zephyr/partition_info.map
SEC_SIDELOAD_KEYS_OFFSET: 0x8FF00
Using ATM OpenOCD 'D:\Project\zephyr\zephyrproject\modules\hal\atmosic_lib\tools\openocd\bin\Windows_NT\openocd'
Inferred OpenOCD config for board 'ATMEVK-3405-WQK-5': D:\Project\zephyr\zephyrproject\zephyr/../openair/modules/hal_atmosic/ATM34xx/rev-5/openocd/atmx3_openocd.cfg
Writing 256 bytes from keys.bin to slots 0-7 in RRAM...
Writing to address 0x8FF00...
Successfully wrote all 256 bytes to slots 0-7

Common Use Cases

Backup and Restore Keys

Backup all keys from device:

west slkey read_all --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -o backup_keys.bin -p build/settings/zephyr/partition_info.map

Restore all keys to device:

west slkey write_all -f backup_keys.bin --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -p build/settings/zephyr/partition_info.map

Update a Single Key

Update only slot 3 with a new key:

west slkey write --slot_index 3 --data 606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -p build/settings/zephyr/partition_info.map

Verify Key Write

Write a key and then read it back to verify:

# Write the key
west slkey write --slot_index 0 --data 10eb3d60be71ca15f0ae732b81777d85072c351fd708613ba310982df4df1409 --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -p build/settings/zephyr/partition_info.map

# Read it back
west slkey read --slot_index 0 --device ATMAPT1000000006 --dl --board ATMEVK-3405-WQK-5 -p build/settings/zephyr/partition_info.map